Objective response rate is a way to measure how many people’s cancers shrink or disappear after treatment. It is usually reported as a percentage of patients who have a complete or partial response. It is commonly used in cancer clinical trials and in oncology research reports. Clinicians may also reference it when discussing how treatments performed in studies.

Time to progression is a way of measuring how long a cancer stays controlled before it grows or spreads again. It is usually reported as a time interval, such as from the start of treatment until objective worsening is found. It is commonly used in oncology clinical trials, research studies, and some quality-improvement reporting. It helps describe treatment effect when overall survival is not yet known or is influenced by later therapies.

Disease-free survival is a way of describing how long a person remains free of detectable cancer after treatment. It is most often used after treatment given with curative intent, such as surgery with or without additional therapy. Clinicians and researchers use it to track recurrence risk over time and to compare treatments in studies. It is commonly reported in oncology clinic follow-up discussions and in clinical trial results.

Event-free survival is a way to measure how long a person remains free of a defined “event” after diagnosis or treatment. An “event” can mean cancer progression, relapse, a second cancer, or death, depending on the study. Event-free survival is commonly used in cancer clinical trials and treatment-outcome reporting. It helps clinicians and researchers compare how well different treatment approaches control cancer over time.

Progression-free survival is the length of time a person lives with cancer without the cancer getting worse. It is commonly used as an outcome measure in oncology clinical trials and in routine cancer follow-up. “Getting worse” usually means the tumor grows, new lesions appear, or cancer-related symptoms and findings clearly progress. Progression-free survival helps describe how long a treatment can keep a cancer under control.

Overall survival is the length of time people are alive after a defined starting point, such as cancer diagnosis or start of treatment. It counts death from any cause, not only death from cancer. Overall survival is widely used in cancer clinical trials and in oncology outcome reporting. It helps clinicians, researchers, and patients understand how treatments and disease factors relate to life expectancy in a population.

Disease control rate is a way to describe how many people in a study have their cancer shrink or stop growing for a period of time. It is commonly reported in oncology clinical trials and sometimes summarized in clinic discussions about treatment response. It combines several response categories into one number to capture “tumor control,” not cure. Its meaning depends on how response is measured and when it is assessed.

Progressive disease is a clinical term that means a cancer is growing, spreading, or worsening over time. It is most commonly used when comparing current tests with a prior “baseline” after diagnosis or treatment. Clinicians use it in routine cancer care and in clinical trials to describe treatment response. The exact definition depends on the cancer type and the response criteria being applied.

Stable disease is a cancer status that means the cancer has not clearly grown or shrunk on assessment. It is commonly used when reviewing scan results, lab trends, and symptoms during or after treatment. Stable disease is one of several standard categories used to describe “response” to therapy. It can apply to solid tumors and blood cancers, although the criteria differ by disease.

Partial response is a term clinicians use to describe how much a cancer has shrunk after treatment. It means the cancer has decreased in size or extent, but it has not completely disappeared. Partial response is commonly used in imaging reports, oncology clinic notes, and clinical trials. It helps standardize communication about treatment effectiveness over time.